Sciencemadness Discussion Board - Large scale amateur alkali buissiness

Large scale amateur alkali buissiness

Reverend Necroticus Rex - 20-3-2005 at 19:08

I am hoping to set up a small buissiness soon, producing alkali metals on a large scale, to sell, for the purposes of boosting up my rather meager income as I am currently on benefit for all the money I get.

The way I intend on doing this, is modifying a series of large fishtanks, to hold anodes at the bottom,
and create a large series of cells with multiple carbon anodes submerged in tanks of pyridine, saturated with caesium, rubidium, potassium and sodium salts, and may create a smaller tank for the preperation of lithium metal, and run it off a generator using cheap fuel, for the caesium, build a tap in the bottom of the tank, to enable running off of the liquid caesium as it is formed, having all the cells containing 20 liters of pyridine, to act as a solvent for electrolysis which will not attack the metal, a closed system, to prevent escape of stinky and toxic pyridine, and a hatch, to permit intake of further metal salts, and an escape valve, built into a single cathode barely touching the surface of the stinky lake of fishy death within, and performing the electrolysis using the chloride salts of the metals.

I have a few questions, and would like input as to optimisations I might make, the cathode will barely touch the pyridine, so that the evolved chlorine gas can simply be run off without reacting with the solvent, therefor minimising maintainance, and then, run off into a large drum kept full of very hot saturated KOH solution, to absorb the Cl2, and also yield large quantities of potassium chlorate as a byproduct, that can be sold for further profit, or perhaps, directly liquify the chlorine in diving gas cylinders, and either sell or use it for my own projects

I hope, to be able to output multiple-tens-of-kilograms quantities of potassium, sodium and caesium metal, and produce rubidium and lithium in any quantity to order, after a first, several kilogram test run of the production process to produce some Rb and Li to be able to satisfy any reasonably sized orders at short notice if I must do.

I would quite like others input on this, I am serious about investing in the stuff needed to create a large-scale home lab manufacture of the group one metals, and equally as serious about selling them for profit, so, if anybody has any suggestions as to how I might improve my setup, I would be very glad to hear of them.

I will probably be selling via Ebay, and, if I manage to get this set up, I will be willing to give any scimadness members, with at least one non-troll post a discout

[Edited on 21-3-2005 by Reverend Necroticus Rex]

BromicAcid - 20-3-2005 at 19:19

From what I have read on electrolysis of the alkali metal salts in pyridine nearly every source that I have found says that electrolysis of lithium salts works better then any of the other alkali metals, one member of our forum Strepta, had this to say in the lithium production thread on it:

Quote:

Last December I thought I'd try the electrolysis of LiCl in pyridine, so I purchased 500ml of pyridine for $60 (ouch!!) I used a graphite anode and a nickel cathode (approx. 2 sq. in.) Spacing between electrodes was about .75 in. I was able to dissolve 2 g of LiCl in 30 ml of pyridine. Applying voltage, I could hardly detect any current flowing. For 30v across the electrodes there was perhaps 15ma of current. The LiCl must not be ionized. Doing a little math after the fact, it takes about 100,000 coulombs to reduce a mole (7 grams) of Li+ ions to Li. At .015A that would take about 2000 hours or much larger plates and I have better things to do. Also, pyridine is not all that pleasant to have around as it smells a lot like skunk. Live and learn I guess.

Larger amounts of pyridine may lead to larger solutions and maybe better current efficency, however if your anode is only going to barely touch the pyridine then your current going through the solution is going to suffer. Because the conductivity of these solutions is so bad usually they use very large flat graphite plates to get the best current out of the system possible. Good luck.

BTW, S.C. Wack followed up to Strepta's post above with this

Quote:

I read his articles (there are later ones in that journal) and thought that there may be some cottage-industryness to it if there was enough demand and cheap electricity. But if I remember correctly, it is a very touchy procedure, for several reasons. The pyridine must be very dry, and stay that way. He did not get good results with the other solvents, either. Would take some work, and this would probably not be a side project, but something you would devote a lot of effort towards, like Kahlenberg did.

[Edited on 3/21/2005 by BromicAcid]

Reverend Necroticus Rex - 20-3-2005 at 19:43

Hmm, what about using a large, flat, slotted or perforated graphite plate, or what about silver, sheets of silver foil could be arranged in large metal frames, to avoid tearing and would give good conduction area for relatively little price.

I think, given low solubility of the salts in pyridine, a co-solvent, mixed with the pyridine might work to imprive the yield,
I am looking up online to see what I can dig up now on the matter of a cosolvent,

I think, perhaps, I would rather use one large tank, to increase efficiency, and prepare one metal at a time, to order, rather than multiple 20-liter tanks, have one, 100 liter tank, with a very large surface area of the electrodes using foil or thin, but large diameter graphite plates.

What about other alkali metal compounds, are the hydroxides soluable in pyridine? although I don't much fancy trying to dry out 100 liters of wet pyridine after the water byproduct of the electrolysis of the hydroxide started to foul things up

rift valley - 20-3-2005 at 21:47

Damn you're not messing around 20L of pyridine goes for around $1400 (US) Gallade Chemical

. Sounds like a big initial investment to get your operation started, but maybe once started it will be easy to maintain? Have you performed experiments involving electrolysis of alkali ions in pyridine before? If you decide to go through with this more power to you :cool:

P.S. Can I put my name on the list for potassium metal please

EDIT: I spoke too soon, it seems 200L can be had for $4500, altough nothing to sneeze at it is still much cheaper then the price I quoted above 200L pyridine

[Edited on 21-3-2005 by rift valley]

The_Davster - 20-3-2005 at 22:05

You may have to go on a smaller scale for the Cs production. Have you checked the prices on any caesium salts lately

S.C. Wack - 20-3-2005 at 22:20

I'm not sure what all articles I was talking about, I didn't keep track of what they were. A quick non-authoritative search yielded:

http://gallica.bnf.fr/catalog?IdentPerio=NP00348

J. Phys. Chem. 3, 602 (1899)
8, 153 (1904)
12, 49 (1908)

but there are others, somewhere. I'm pretty sure this isn't going to happen.

Reverend Necroticus Rex - 20-3-2005 at 22:28

Well, my father is arranging to get me 100ml or so of pyridine hopefully, to do some preliminary testing and experimentation, to find a decent co-solvent to ionise the salts more efficiently.

He said to me, he is willing to help, even to the extent of me getting a small shed to function as a lab, so long as I can produce, and sell, a small sample of an alkali metal, I am thinking ten grams or so to begin with for proof of concept.

Rogue Chemist, I noticed, that the link you provided for pyridine, was of the ACS grade, I am sure pyridine can be had for cheaper, it doesn't need to be analytical grade of course, merely anhydrous.

Can pyridine be distilled over CaCl2? or are molecular sives needed for drying?

SC.Whack, you couldn't perhaps post the full text of those journal references could you, I can only access the abstracts, which provide no information.

[Edited on 21-3-2005 by Reverend Necroticus Rex]

[Edited on 21-3-2005 by Reverend Necroticus Rex]

The_Davster - 20-3-2005 at 23:11

Reverend, you gave the credit to the wrong guy, rift valley linked you to the pyridine page.

I did a bit of looking around and cesium salts range in price from 1-2$ per gram

. You might to make sure your setup works well with the other alkalis first before you invest in large ammounts of cesium compounds.

Antwain - 10-10-2007 at 04:06

Sorry to revive an old thread and hijack it good but this last post is EXACTLY my problem.

WHY IN THE HELL IS CAESIUM SO GODDAM EXPENSIVE?

According to Wiki (I will trust it since they have multiple sources and differnt values in good agreement) it is ~10^2 times more prevalent in the crust than silver. 1/5 as abundant as bromine!!!!!!!!!!

Bromine is going to be found in the same places as caesium, ie salt deposits. So why are we being reamed, and where can we go to not get reamed?

evil_lurker - 10-10-2007 at 07:01

It could be that there is not a very large market for it, and quite possibly it presents purification issues.

not_important - 10-10-2007 at 07:29

Caesium is so expensive in part because unlike silver it doesn't concentrate in ores that much, and it's not nearly as easy as silver to isolate as an element or a compound of the element.

For silver a number of relatively simple chemical or thermochemical processes will give a crude high silver alloy. After that electrorefining using aqueous electrolyte will give both pure silver and a byproduct of any gold and platinum metals that were in the crude alloy. Similarly electrorefining of copper gives a byproduct of the precious metal content of the original ore.

Caesium, rubidium, and potassium stick together pretty well, in most places the concentration of Cs and Rb are rather low, and there's generally a lot of sodium and lithium as well. It's just in a few alkali metal rich rocks that the Cs and Rb concentration is high enough to make it worth going after. Bernic Lake in Canada has about 2/3 of the world's reserves of economically extractable caesium ore. And once you got the Cs and Rb out, you have to isolate them via fractional crystallisation or other process that doesn't give clean separation in a single step.

Bromine is easy to extract from fairly dilute sources, blow chlorine and steam through the solution and collect the bromine vapours. Bromine is extracted from brines with 4 to 5 parts per thousand of bromine, a fairly low concentration of target for most elements.

When it comes to elements or simple compounds, high prices generally don't mean you're being ripped off, but that it's difficult to obtain them and/or the demand is low enough that extraction is on a small scale and hasn't been optimised. Caesium format drilling fluid runs some 4000 $US per barrel, meaning that many operations use some alternative rather than showering the suppliers with their money; I'm sure the suppliers would like to have a way to reduce the cost so they could sell more.

kilowatt - 16-10-2007 at 20:44

You could always make your own pyridine from ammonia or ammonium acetate (easy to make from the obvious), acetaldehyde (could be made through partial oxidation of ethanol), and formaldehyde (easily purchased in the form of trioxane fuel tablets). http://en.wikipedia.org/wiki/Hantzsch_pyridine_synthesis

You can get cesium chloride for $235/kilo plus shipping (bringing it to about $250) from cesium-chloride.com, but...

If this pyridine electrolysis could be used at all to make the more reactive alkali metals, potassium, rubidium, and cesium, wouldn't they use it industrially instead of fractional distillation of the metal from a fused salt bath with addition of liquid sodium? That process requires high temperature, relatively complex apparatus, and has fairly low batch yield, with a continuous process involving continual removal of the fused salt and fractional crystallization, prior to the addition of new salt. Especially considering the low demand of these metals and the fact that pyridine is produced from such fundamental reagents, they would probably use it if it was even possible.

vulture - 16-10-2007 at 22:23

Not really. Large quantities of pyridine would present difficulties that industries like to avoid: toxicity, environmental problems, flammability, volatility.

kilowatt - 16-10-2007 at 22:58

It isn't as flammable, toxic, or otherwise insanely hazardous as cesium vapor...

[Edited on 16-10-2007 by kilowatt]

vulture - 16-10-2007 at 23:46

Pyridine is both HIGHLY flammable and harmful. You'd better check an MSDS before messing around.

Other than that, Cesium is the desired product and can be sold. You don't want thousands of liters of harmful and flammable solvent in an industrial environment which have to be processed and disposed of.

[Edited on 17-10-2007 by vulture]

kilowatt - 17-10-2007 at 00:50

I guess I'm not sure what the point of any of this is. Many industrial processes use dangerous reagents or equipment. Pyridine is nasty stuff but certainly not alarming. It is mere childsplay compared with HCN, cyanogen, boranes, hydrazine, arsine, and many other industrial chemicals. They usually use the most cost-effective method, but you're correct that environmental concerns can be an issue too. A large bath of pyridine is certainly harder to legitimately dispose of than a batch of harmless salts at the end of the day.

Personally I am skeptical that this cold electrolysis method is viable, and its lack of use in industry is one reason why. However I do wish the best of luck to anyone who tries it and would like to see some actual experiments with it. If cesium salts are relatively soluble in pyridine and it will not react with cesium metal, it just might work out. I have too many other chemistry projects going now to even think about it, though. Being in school, away from my lab, does not help.

vulture - 17-10-2007 at 03:47

Don't look at the industry for lab scale preparations. The industry uses processes that are totally uneconomical (Haber-Bosch for example) on a lab scale but work in large quantities. In a lab you'd make ammonia from an ammonium salt and a base, in the industry this is considered nuts.

Quote:

It is mere childsplay compared with HCN, cyanogen, boranes, hydrazine, arsine, and many other industrial chemicals.

Correct, but they are usually a reagent which is consumed or for which there is no viable alternative. Neither is the case for pyridine.